Several methods and machines for forming aseptic and non aseptic packages or cartons from paper stock and laminated web packaging materials are known. These methods and machines generally fall into two categories. In the first category, packages are made on blank fed machines wherein the supply of web is first separately formed into cut and scored blanks. The blanks are then fed into the forming section of the machine one at a time and erected into containers, filled, and sealed. For aseptic packaging, the containers are sterilized, filled with a sterile product while in a sterile environment, and sealed hermetically closed. In the process of forming finished sealed containers, the excess packaging material may be tacked, i.e., flattened against adjacent package panels and secured thereto, to provide a substantially smooth package surface that is convenient for handling, bundling, and storage.
The blank fed machines typically operate intermittently, performing one assembly step at a station and then advancing the blank or carton to the next station for the next operation. Other blank fed machines may operate semi-continuously, for example, continuously advancing the blank to form the container and then intermittently advancing the container to sterilize, fill, and seal the con tainer and fold and tack flat against the container walls the excess packaging material created by sealing and bricking of the package as the package moves along its path of travel. One commercial intermittent type blank fed aseptic machine is Combiblok Model No. CF 606A, Columbus, Ohio.
The second category of package forming machines are those that use web from a continuous roll and advance the web to form, fill, seal, and sever the packages. In these machines, the web is taken directly off the roll of web stock, scored (unless prescored on the roll) and fed into the machine. The machine then folds the web to form a column, seals the longitudinal edge to form a tube, fills the tube with a product, and clamps, seals, and severs the tube to form the packages. The packages are then operated upon to form them into the desired final configuration, e.g., a rectangular brick, by folding and tacking the excess packaging material in the package corners and seams securely against the package panels. The web advance may be continuous to gradually manipulate the web into sealed packages, or intermittent so that each assembly operation is performed at a different station while the web is stationary, or while the web is moving between stations.
For aseptic packaging, the web is sterilized, fed into a sterile machine zone, and appropriately, filled with the product in a sterile environment, and sealed to maintain sterility. One commercial automatic continuous feed aseptic machine is Tetra-Pak Model AB 9. Other known aseptic machines include International Paper Co.'s web fed aseptic package machine, Model SA.
Reciprocating means may be used to operate on the web or packages, either first, reciprocating into position and operation when the web or package is stationary and reciprocating out of position and operation when the web or package is advanced, or second, reciprocating with and operating on the web or package as it advances and then, at the end of its stroke range, reciprocating back to the beginning of its stroke while the web or package is stationary. Reciprocating means must return to a point of origin at the beginning of its stroke range before working on the next section of web. There may be one or more reciprocating means which reciprocate while the web or severed packages continue to advance. Alternately, opposing endlessly rotating means may be used such as wheels or endless linked belts containing a plurality of identical means for sequentially operating on the web or packages as the web or packages advance at a substantially uniform speed. The present invention relates to an improvement in continuous feed type machines, and is designed to have a production rate substantially higher than that of presently known machines, for example, greater than 10,000 quarter liter packages per hour.
The primary problem with the aforementioned machines is that they are limited in the machine speed and material control required to continuously or intermittently make aseptic packages at a rate of speed higher than presently obtainable in an economically efficient manner. One specific problem with the known machines is the time required to provide a package that can be easily bundled or stored and is esthetically acceptable to the consumer. Finishing the package typically requires folding the tabs and, optionally, seams, created during the forming, filling, and severing steps to make a commercially acceptable square or rectangular final carton at the desired high rates of production. The aforementioned machines may require indexing one or more carousels which operate on the package while it is stationary as the package is advanced through a series of work stations. Indexing carousels are limited in speed because of the time limits imposed in operating on and advancing the packages incrementally for each successive operation.
Merely increasing the frequency of reciprocation or indexed advance to increase the rate of production would increase wear and may not provide sufficient time to satisfactorily tack the seams and tabs. Further, rapid start and stops could cause such an apparatus to shake itself apart. Adding a second reciprocating device to increase the volume of production could be used. However, this technique does not increase the reciprocation or production rates and adds undue mechanical complexity to distribute the sealed packages to the carousels alternately or to permit plural means to operate simultaneously, out of phase. Adding further tab folding apparatus to accommodate finishing more packages per hour from a single form, fill and seal machine becomes even more complex and difficult.
Moreover, adding a second or multiple production lines does not solve the problem of increasing the production rate of a single machine. Multiple production lines mounted on a common frame may achieve some efficiencies in reducing the number of product supply means, drive means, and the like, but it is effectively the same as two or multiple machines and can require multiple package handling equipment devices such as straw applicators, six pack package bundling equipment, and may require dedicated sterile air sources, one such device for each line. The rate of production is not increased, only the volume. Such machines, e.g., the aforementioned Combiblok machine which has two parallel production lines, and other known models which have four production lines, are unduly bulky, complicated mechanically, and occupy a substantial amount of floor space. Further, the more common elements shared by the multiple lines, the more complicated and expensive the machine becomes, especially if the entire machine must be stopped to fix a problem present in only one of the lines.
It is therefore an object of this invention to provide a method and apparatus for folding and tacking the excess packaging material and bricking each package into its final form as the package advances continuously at high rates of speed.